code: def test_nested(self, cls_ofg):
      x, y = T.vectors("xy")
      u, v = x + y, x - y
      op_ft = cls_ofg([x, y], [u, v])
      op_ift = cls_ofg([x, y], [u / 2, v / 2])
  
      xx, yy = T.vector("xx"), T.vector("yy")
      xx2, yy2 = op_ift(*op_ft(xx, yy))
      fn = function([xx, yy], [xx2, yy2])
  
      xv = np.random.rand(16).astype(config.floatX)
      yv = np.random.rand(16).astype(config.floatX)
      xv2, yv2 = fn(xv, yv)
      assert np.allclose(xv, xv2)
      assert np.allclose(yv, yv2)
  
imports: from __future__ import absolute_import, print_function, division
  from functools import partial
  import numpy
  import theano
  from theano import config, shared
  from theano.gradient import DisconnectedType
  from theano.gof.null_type import NullType
  from theano.compile import function
  from theano import tensor
  from theano.tensor.shared_randomstreams import RandomStreams
  from theano.compile.builders import OpFromGraph
  from theano.tests import unittest_tools
label_desc: Use image node_id 12 for calling the T_OpFromGraph obj's underlying member method code with example usage: obj.test_nested(cls_ofg) without return types